The treatment of meniscus defects represents one of the great challenges in orthopedics and accident surgery. It had long been held that destruction of the meniscal structures is irreversible and that total restoration “restitutio ad integrum” is no longer possible.
There have in the meantime been a series of good attempts at the treatment of meniscus defects. As before, however, only a few suitable implants are available so far. In some cases, meniscus transplants from donor bodies are also used. It is disadvantageous, however, that the material concerned is dead and therefore can only be revitalized under certain conditions.
A key problem with meniscus reconstructions is the stable anchorage of the implant or transplant. Since perfusion of the meniscus takes place from what is known as the base, i.e., from the side of the meniscus facing the articular capsule, every implant or transplant must be anchored as firmly as possible by its base to this articular capsule or cartilage rim. If stable anchorage on the articular capsule does not occur, it may be the case, for example, that a transplant is not revitalized. Stable anchorage in the healing phase, in the sense of close contact between the meniscus transplant or implant and the articular capsule, must also additionally withstand movements of the joint.
Usually, implants or transplants used for meniscus reconstruction are fixed to the articular capsule by a similar technique to that also used for treating meniscus ruptures. In this technique, the implants or transplants are sewn in with threads or attached to the articular capsule by suitable anchoring elements. In this case, the anchoring elements are fired into the articular capsule through the meniscus to be attached, the implant to be attached or the transplant to be attached. A particular problem here is also fixing the end points of a meniscus implant or transplant. One of the usual fixing techniques is to reinforce the end points with the threads and anchor the threads in the tibial bone.
In spite of all these efforts, the results achieved in the treatment of cartilage and meniscus defects are still not satisfactory. In particular, the treatment methods described above are laborious and time-consuming. It is even often necessary for the joint to be partially opened in an arthrotomy procedure. Furthermore, it is often technically very difficult to use arthroscopic means for introducing anchoring elements into the desired position. In US 2008/0086210 A1, anchorage elements for anchoring the artificial meniscus described there engage in a groove in the tibial bone, which is difficult to carry out intraoperatively. Furthermore, the anchorage does not take place on the articular capsule but on the articular bone.
It could therefore be helpful to provide an implant for meniscus reconstruction that allows the most stable possible anchorage or fixing on the articular capsule (cartilage rim) of a patient. In addition, the implant should be as easy as possible to implant, in particular by arthroscopic methods.